Merge isolates to bleeding_edge.

src/top.h

Index: src/top.h
===================================================================
--- src/top.h	(revision 7267)
+++ src/top.h	(working copy)
@@ -1,608 +0,0 @@
-// Copyright 2006-2008 the V8 project authors. All rights reserved.
-// Redistribution and use in source and binary forms, with or without
-// modification, are permitted provided that the following conditions are
-// met:
-//
-//     * Redistributions of source code must retain the above copyright
-//       notice, this list of conditions and the following disclaimer.
-//     * Redistributions in binary form must reproduce the above
-//       copyright notice, this list of conditions and the following
-//       disclaimer in the documentation and/or other materials provided
-//       with the distribution.
-//     * Neither the name of Google Inc. nor the names of its
-//       contributors may be used to endorse or promote products derived
-//       from this software without specific prior written permission.
-//
-// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
-// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
-// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
-// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
-// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
-// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
-// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
-// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
-// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
-// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
-// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
-
-#ifndef V8_TOP_H_
-#define V8_TOP_H_
-
-#include "atomicops.h"
-#include "compilation-cache.h"
-#include "frames-inl.h"
-#include "runtime-profiler.h"
-
-namespace v8 {
-namespace internal {
-
-class Simulator;
-
-#define RETURN_IF_SCHEDULED_EXCEPTION() \
-  if (Top::has_scheduled_exception()) return Top::PromoteScheduledException()
-
-#define RETURN_IF_EMPTY_HANDLE_VALUE(call, value) \
-  if (call.is_null()) {                           \
-    ASSERT(Top::has_pending_exception());         \
-    return value;                                 \
-  }
-
-#define RETURN_IF_EMPTY_HANDLE(call)      \
-  RETURN_IF_EMPTY_HANDLE_VALUE(call, Failure::Exception())
-
-// Top has static variables used for JavaScript execution.
-
-class SaveContext;  // Forward declaration.
-class ThreadVisitor;  // Defined in v8threads.h
-class VMState;  // Defined in vm-state.h
-
-class ThreadLocalTop BASE_EMBEDDED {
- public:
-  // Initialize the thread data.
-  void Initialize();
-
-  // Get the top C++ try catch handler or NULL if none are registered.
-  //
-  // This method is not guarenteed to return an address that can be
-  // used for comparison with addresses into the JS stack.  If such an
-  // address is needed, use try_catch_handler_address.
-  v8::TryCatch* TryCatchHandler();
-
-  // Get the address of the top C++ try catch handler or NULL if
-  // none are registered.
-  //
-  // This method always returns an address that can be compared to
-  // pointers into the JavaScript stack.  When running on actual
-  // hardware, try_catch_handler_address and TryCatchHandler return
-  // the same pointer.  When running on a simulator with a separate JS
-  // stack, try_catch_handler_address returns a JS stack address that
-  // corresponds to the place on the JS stack where the C++ handler
-  // would have been if the stack were not separate.
-  inline Address try_catch_handler_address() {
-    return try_catch_handler_address_;
-  }
-
-  // Set the address of the top C++ try catch handler.
-  inline void set_try_catch_handler_address(Address address) {
-    try_catch_handler_address_ = address;
-  }
-
-  void Free() {
-    ASSERT(!has_pending_message_);
-    ASSERT(!external_caught_exception_);
-    ASSERT(try_catch_handler_address_ == NULL);
-  }
-
-  // The context where the current execution method is created and for variable
-  // lookups.
-  Context* context_;
-  int thread_id_;
-  MaybeObject* pending_exception_;
-  bool has_pending_message_;
-  const char* pending_message_;
-  Object* pending_message_obj_;
-  Script* pending_message_script_;
-  int pending_message_start_pos_;
-  int pending_message_end_pos_;
-  // Use a separate value for scheduled exceptions to preserve the
-  // invariants that hold about pending_exception.  We may want to
-  // unify them later.
-  MaybeObject* scheduled_exception_;
-  bool external_caught_exception_;
-  SaveContext* save_context_;
-  v8::TryCatch* catcher_;
-
-  // Stack.
-  Address c_entry_fp_;  // the frame pointer of the top c entry frame
-  Address handler_;   // try-blocks are chained through the stack
-
-#ifdef USE_SIMULATOR
-#ifdef V8_TARGET_ARCH_ARM
-  Simulator* simulator_;
-#elif V8_TARGET_ARCH_MIPS
-  assembler::mips::Simulator* simulator_;
-#endif
-#endif  // USE_SIMULATOR
-
-#ifdef ENABLE_LOGGING_AND_PROFILING
-  Address js_entry_sp_;  // the stack pointer of the bottom js entry frame
-  Address external_callback_;  // the external callback we're currently in
-#endif
-
-#ifdef ENABLE_VMSTATE_TRACKING
-  StateTag current_vm_state_;
-
-  // Used for communication with the runtime profiler thread.
-  // Possible values are specified in RuntimeProfilerState.
-  Atomic32 runtime_profiler_state_;
-#endif
-
-  // Generated code scratch locations.
-  int32_t formal_count_;
-
-  // Call back function to report unsafe JS accesses.
-  v8::FailedAccessCheckCallback failed_access_check_callback_;
-
- private:
-  Address try_catch_handler_address_;
-};
-
-#define TOP_ADDRESS_LIST(C)            \
-  C(handler_address)                   \
-  C(c_entry_fp_address)                \
-  C(context_address)                   \
-  C(pending_exception_address)         \
-  C(external_caught_exception_address)
-
-#ifdef ENABLE_LOGGING_AND_PROFILING
-#define TOP_ADDRESS_LIST_PROF(C)       \
-  C(js_entry_sp_address)
-#else
-#define TOP_ADDRESS_LIST_PROF(C)
-#endif
-
-
-class Top {
- public:
-  enum AddressId {
-#define C(name) k_##name,
-    TOP_ADDRESS_LIST(C)
-    TOP_ADDRESS_LIST_PROF(C)
-#undef C
-    k_top_address_count
-  };
-
-  static Address get_address_from_id(AddressId id);
-
-  // Access to top context (where the current function object was created).
-  static Context* context() { return thread_local_.context_; }
-  static void set_context(Context* context) {
-    thread_local_.context_ = context;
-  }
-  static Context** context_address() { return &thread_local_.context_; }
-
-  static SaveContext* save_context() {return thread_local_.save_context_; }
-  static void set_save_context(SaveContext* save) {
-    thread_local_.save_context_ = save;
-  }
-
-  // Access to current thread id.
-  static int thread_id() { return thread_local_.thread_id_; }
-  static void set_thread_id(int id) { thread_local_.thread_id_ = id; }
-
-  // Interface to pending exception.
-  static MaybeObject* pending_exception() {
-    ASSERT(has_pending_exception());
-    return thread_local_.pending_exception_;
-  }
-  static bool external_caught_exception() {
-    return thread_local_.external_caught_exception_;
-  }
-  static void set_pending_exception(MaybeObject* exception) {
-    thread_local_.pending_exception_ = exception;
-  }
-  static void clear_pending_exception() {
-    thread_local_.pending_exception_ = Heap::the_hole_value();
-  }
-
-  static MaybeObject** pending_exception_address() {
-    return &thread_local_.pending_exception_;
-  }
-  static bool has_pending_exception() {
-    return !thread_local_.pending_exception_->IsTheHole();
-  }
-  static void clear_pending_message() {
-    thread_local_.has_pending_message_ = false;
-    thread_local_.pending_message_ = NULL;
-    thread_local_.pending_message_obj_ = Heap::the_hole_value();
-    thread_local_.pending_message_script_ = NULL;
-  }
-  static v8::TryCatch* try_catch_handler() {
-    return thread_local_.TryCatchHandler();
-  }
-  static Address try_catch_handler_address() {
-    return thread_local_.try_catch_handler_address();
-  }
-  // This method is called by the api after operations that may throw
-  // exceptions.  If an exception was thrown and not handled by an external
-  // handler the exception is scheduled to be rethrown when we return to running
-  // JavaScript code.  If an exception is scheduled true is returned.
-  static bool OptionalRescheduleException(bool is_bottom_call);
-
-
-  static bool* external_caught_exception_address() {
-    return &thread_local_.external_caught_exception_;
-  }
-
-  static MaybeObject** scheduled_exception_address() {
-    return &thread_local_.scheduled_exception_;
-  }
-
-  static MaybeObject* scheduled_exception() {
-    ASSERT(has_scheduled_exception());
-    return thread_local_.scheduled_exception_;
-  }
-  static bool has_scheduled_exception() {
-    return !thread_local_.scheduled_exception_->IsTheHole();
-  }
-  static void clear_scheduled_exception() {
-    thread_local_.scheduled_exception_ = Heap::the_hole_value();
-  }
-
-  static bool IsExternallyCaught();
-
-  static void SetCaptureStackTraceForUncaughtExceptions(
-      bool capture,
-      int frame_limit,
-      StackTrace::StackTraceOptions options);
-
-  // Tells whether the current context has experienced an out of memory
-  // exception.
-  static bool is_out_of_memory();
-
-  static bool is_catchable_by_javascript(MaybeObject* exception) {
-    return (exception != Failure::OutOfMemoryException()) &&
-        (exception != Heap::termination_exception());
-  }
-
-  // JS execution stack (see frames.h).
-  static Address c_entry_fp(ThreadLocalTop* thread) {
-    return thread->c_entry_fp_;
-  }
-  static Address handler(ThreadLocalTop* thread) { return thread->handler_; }
-
-  static inline Address* c_entry_fp_address() {
-    return &thread_local_.c_entry_fp_;
-  }
-  static inline Address* handler_address() { return &thread_local_.handler_; }
-
-#ifdef ENABLE_LOGGING_AND_PROFILING
-  // Bottom JS entry (see StackTracer::Trace in log.cc).
-  static Address js_entry_sp(ThreadLocalTop* thread) {
-    return thread->js_entry_sp_;
-  }
-  static inline Address* js_entry_sp_address() {
-    return &thread_local_.js_entry_sp_;
-  }
-
-  static Address external_callback() {
-    return thread_local_.external_callback_;
-  }
-  static void set_external_callback(Address callback) {
-    thread_local_.external_callback_ = callback;
-  }
-#endif
-
-#ifdef ENABLE_VMSTATE_TRACKING
-  static StateTag current_vm_state() {
-    return thread_local_.current_vm_state_;
-  }
-
-  static void SetCurrentVMState(StateTag state) {
-    if (RuntimeProfiler::IsEnabled()) {
-      if (state == JS) {
-        // JS or non-JS -> JS transition.
-        RuntimeProfilerState old_state = SwapRuntimeProfilerState(PROF_IN_JS);
-        if (old_state == PROF_NOT_IN_JS_WAITING_FOR_JS) {
-          // If the runtime profiler was waiting, we reset the eager
-          // optimizing data in the compilation cache to get a fresh
-          // start after not running JavaScript code for a while and
-          // signal the runtime profiler so it can resume.
-          CompilationCache::ResetEagerOptimizingData();
-          runtime_profiler_semaphore_->Signal();
-        }
-      } else if (thread_local_.current_vm_state_ == JS) {
-        // JS -> non-JS transition. Update the runtime profiler state.
-        ASSERT(IsInJSState());
-        SetRuntimeProfilerState(PROF_NOT_IN_JS);
-      }
-    }
-    thread_local_.current_vm_state_ = state;
-  }
-
-  // Called in the runtime profiler thread.
-  // Returns whether the current VM state is set to JS.
-  static bool IsInJSState() {
-    ASSERT(RuntimeProfiler::IsEnabled());
-    return static_cast<RuntimeProfilerState>(
-        NoBarrier_Load(&thread_local_.runtime_profiler_state_)) == PROF_IN_JS;
-  }
-
-  // Called in the runtime profiler thread.
-  // Waits for the VM state to transtion from non-JS to JS. Returns
-  // true when notified of the transition, false when the current
-  // state is not the expected non-JS state.
-  static bool WaitForJSState() {
-    ASSERT(RuntimeProfiler::IsEnabled());
-    // Try to switch to waiting state.
-    RuntimeProfilerState old_state = CompareAndSwapRuntimeProfilerState(
-        PROF_NOT_IN_JS, PROF_NOT_IN_JS_WAITING_FOR_JS);
-    if (old_state == PROF_NOT_IN_JS) {
-      runtime_profiler_semaphore_->Wait();
-      return true;
-    }
-    return false;
-  }
-
-  // When shutting down we join the profiler thread. Doing so while
-  // it's waiting on a semaphore will cause a deadlock, so we have to
-  // wake it up first.
-  static void WakeUpRuntimeProfilerThreadBeforeShutdown() {
-    runtime_profiler_semaphore_->Signal();
-  }
-#endif
-
-  // Generated code scratch locations.
-  static void* formal_count_address() { return &thread_local_.formal_count_; }
-
-  static void PrintCurrentStackTrace(FILE* out);
-  static void PrintStackTrace(FILE* out, char* thread_data);
-  static void PrintStack(StringStream* accumulator);
-  static void PrintStack();
-  static Handle<String> StackTraceString();
-  static Handle<JSArray> CaptureCurrentStackTrace(
-      int frame_limit,
-      StackTrace::StackTraceOptions options);
-
-  // Returns if the top context may access the given global object. If
-  // the result is false, the pending exception is guaranteed to be
-  // set.
-  static bool MayNamedAccess(JSObject* receiver,
-                             Object* key,
-                             v8::AccessType type);
-  static bool MayIndexedAccess(JSObject* receiver,
-                               uint32_t index,
-                               v8::AccessType type);
-
-  static void SetFailedAccessCheckCallback(
-      v8::FailedAccessCheckCallback callback);
-  static void ReportFailedAccessCheck(JSObject* receiver, v8::AccessType type);
-
-  // Exception throwing support. The caller should use the result
-  // of Throw() as its return value.
-  static Failure* Throw(Object* exception, MessageLocation* location = NULL);
-  // Re-throw an exception.  This involves no error reporting since
-  // error reporting was handled when the exception was thrown
-  // originally.
-  static Failure* ReThrow(MaybeObject* exception,
-                          MessageLocation* location = NULL);
-  static void ScheduleThrow(Object* exception);
-  static void ReportPendingMessages();
-  static Failure* ThrowIllegalOperation();
-
-  // Promote a scheduled exception to pending. Asserts has_scheduled_exception.
-  static Failure* PromoteScheduledException();
-  static void DoThrow(MaybeObject* exception,
-                      MessageLocation* location,
-                      const char* message);
-  // Checks if exception should be reported and finds out if it's
-  // caught externally.
-  static bool ShouldReportException(bool* can_be_caught_externally,
-                                    bool catchable_by_javascript);
-
-  // Attempts to compute the current source location, storing the
-  // result in the target out parameter.
-  static void ComputeLocation(MessageLocation* target);
-
-  // Override command line flag.
-  static void TraceException(bool flag);
-
-  // Out of resource exception helpers.
-  static Failure* StackOverflow();
-  static Failure* TerminateExecution();
-
-  // Administration
-  static void Initialize();
-  static void TearDown();
-  static void Iterate(ObjectVisitor* v);
-  static void Iterate(ObjectVisitor* v, ThreadLocalTop* t);
-  static char* Iterate(ObjectVisitor* v, char* t);
-  static void IterateThread(ThreadVisitor* v);
-  static void IterateThread(ThreadVisitor* v, char* t);
-
-  // Returns the global object of the current context. It could be
-  // a builtin object, or a js global object.
-  static Handle<GlobalObject> global() {
-    return Handle<GlobalObject>(context()->global());
-  }
-
-  // Returns the global proxy object of the current context.
-  static Object* global_proxy() {
-    return context()->global_proxy();
-  }
-
-  // Returns the current global context.
-  static Handle<Context> global_context();
-
-  // Returns the global context of the calling JavaScript code.  That
-  // is, the global context of the top-most JavaScript frame.
-  static Handle<Context> GetCallingGlobalContext();
-
-  static Handle<JSBuiltinsObject> builtins() {
-    return Handle<JSBuiltinsObject>(thread_local_.context_->builtins());
-  }
-
-  static void RegisterTryCatchHandler(v8::TryCatch* that);
-  static void UnregisterTryCatchHandler(v8::TryCatch* that);
-
-#define TOP_GLOBAL_CONTEXT_FIELD_ACCESSOR(index, type, name)  \
-  static Handle<type> name() {                                \
-    return Handle<type>(context()->global_context()->name()); \
-  }
-  GLOBAL_CONTEXT_FIELDS(TOP_GLOBAL_CONTEXT_FIELD_ACCESSOR)
-#undef TOP_GLOBAL_CONTEXT_FIELD_ACCESSOR
-
-  static inline ThreadLocalTop* GetCurrentThread() { return &thread_local_; }
-  static int ArchiveSpacePerThread() { return sizeof(ThreadLocalTop); }
-  static char* ArchiveThread(char* to);
-  static char* RestoreThread(char* from);
-  static void FreeThreadResources() { thread_local_.Free(); }
-
-  static const char* kStackOverflowMessage;
-
- private:
-#ifdef ENABLE_VMSTATE_TRACKING
-  // Set of states used when communicating with the runtime profiler.
-  //
-  // The set of possible transitions is divided between the VM and the
-  // profiler threads.
-  //
-  // The VM thread can perform these transitions:
-  //   o IN_JS -> NOT_IN_JS
-  //   o NOT_IN_JS -> IN_JS
-  //   o NOT_IN_JS_WAITING_FOR_JS -> IN_JS notifying the profiler thread
-  //     using the semaphore.
-  // All the above transitions are caused by VM state changes.
-  //
-  // The profiler thread can only perform a single transition
-  // NOT_IN_JS -> NOT_IN_JS_WAITING_FOR_JS before it starts waiting on
-  // the semaphore.
-  enum RuntimeProfilerState {
-    PROF_NOT_IN_JS,
-    PROF_NOT_IN_JS_WAITING_FOR_JS,
-    PROF_IN_JS
-  };
-
-  static void SetRuntimeProfilerState(RuntimeProfilerState state) {
-    NoBarrier_Store(&thread_local_.runtime_profiler_state_, state);
-  }
-
-  static RuntimeProfilerState SwapRuntimeProfilerState(
-      RuntimeProfilerState state) {
-    return static_cast<RuntimeProfilerState>(
-        NoBarrier_AtomicExchange(&thread_local_.runtime_profiler_state_,
-                                 state));
-  }
-
-  static RuntimeProfilerState CompareAndSwapRuntimeProfilerState(
-      RuntimeProfilerState old_state,
-      RuntimeProfilerState state) {
-    return static_cast<RuntimeProfilerState>(
-        NoBarrier_CompareAndSwap(&thread_local_.runtime_profiler_state_,
-                                 old_state,
-                                 state));
-  }
-
-  static Semaphore* runtime_profiler_semaphore_;
-#endif  // ENABLE_VMSTATE_TRACKING
-
-  // The context that initiated this JS execution.
-  static ThreadLocalTop thread_local_;
-  static void InitializeThreadLocal();
-  static void PrintStackTrace(FILE* out, ThreadLocalTop* thread);
-  static void MarkCompactPrologue(bool is_compacting,
-                                  ThreadLocalTop* archived_thread_data);
-  static void MarkCompactEpilogue(bool is_compacting,
-                                  ThreadLocalTop* archived_thread_data);
-
-  // Debug.
-  // Mutex for serializing access to break control structures.
-  static Mutex* break_access_;
-
-  friend class SaveContext;
-  friend class AssertNoContextChange;
-  friend class ExecutionAccess;
-  friend class ThreadLocalTop;
-
-  static void FillCache();
-};
-
-
-// If the GCC version is 4.1.x or 4.2.x an additional field is added to the
-// class as a work around for a bug in the generated code found with these
-// versions of GCC. See V8 issue 122 for details.
-class SaveContext BASE_EMBEDDED {
- public:
-  SaveContext()
-      : context_(Top::context()),
-#if __GNUC_VERSION__ >= 40100 && __GNUC_VERSION__ < 40300
-        dummy_(Top::context()),
-#endif
-        prev_(Top::save_context()) {
-    Top::set_save_context(this);
-
-    // If there is no JS frame under the current C frame, use the value 0.
-    JavaScriptFrameIterator it;
-    js_sp_ = it.done() ? 0 : it.frame()->sp();
-  }
-
-  ~SaveContext() {
-    Top::set_context(*context_);
-    Top::set_save_context(prev_);
-  }
-
-  Handle<Context> context() { return context_; }
-  SaveContext* prev() { return prev_; }
-
-  // Returns true if this save context is below a given JavaScript frame.
-  bool below(JavaScriptFrame* frame) {
-    return (js_sp_ == 0) || (frame->sp() < js_sp_);
-  }
-
- private:
-  Handle<Context> context_;
-#if __GNUC_VERSION__ >= 40100 && __GNUC_VERSION__ < 40300
-  Handle<Context> dummy_;
-#endif
-  SaveContext* prev_;
-  Address js_sp_;  // The top JS frame's sp when saving context.
-};
-
-
-class AssertNoContextChange BASE_EMBEDDED {
-#ifdef DEBUG
- public:
-  AssertNoContextChange() :
-      context_(Top::context()) {
-  }
-
-  ~AssertNoContextChange() {
-    ASSERT(Top::context() == *context_);
-  }
-
- private:
-  HandleScope scope_;
-  Handle<Context> context_;
-#else
- public:
-  AssertNoContextChange() { }
-#endif
-};
-
-
-class ExecutionAccess BASE_EMBEDDED {
- public:
-  ExecutionAccess() { Lock(); }
-  ~ExecutionAccess() { Unlock(); }
-
-  static void Lock() { Top::break_access_->Lock(); }
-  static void Unlock() { Top::break_access_->Unlock(); }
-
-  static bool TryLock() {
-    return Top::break_access_->TryLock();
-  }
-};
-
-} }  // namespace v8::internal
-
-#endif  // V8_TOP_H_